Testicular Cancer
Testicular cancer is a malignancy arising within the testis, most often from the germ cells that produce sperm. It is uncommon in absolute terms but is the most frequently diagnosed solid cancer in men between roughly 15 and 40, an age group in which cancer of any kind is rare. It typically presents as a painless lump or firm area in the testis, and the absence of pain is the main reason men delay seeking assessment. What sets this cancer apart is its response to treatment: cure rates are among the highest of any malignancy, and even men who present with disease that has already spread widely have a substantial chance of complete cure with modern chemotherapy. Prompt assessment matters, but so does knowing that the outlook is generally very good.
What is it?
The testes produce sperm and testosterone. Sperm develop from germ cells within a network of fine tubules, supported by Sertoli cells, while Leydig cells in the surrounding tissue produce testosterone. Cancer can arise from any of these cell populations, but germ cells account for the overwhelming majority.
Germ cell tumours are thought to originate from a precursor lesion called germ cell neoplasia in situ, which develops from fetal germ cells that fail to mature normally. This origin explains several features of the disease: why it affects young men, why it is associated with conditions affecting testicular development such as undescended testis and impaired fertility, and why some researchers group these together under the heading of testicular dysgenesis syndrome.
Germ cell tumours divide into two categories that behave and are treated differently, and this distinction shapes everything downstream.
Seminomas arise from cells that resemble immature germ cells. They occur at a slightly older average age, often in the fourth decade, tend to grow more slowly, spread predictably through lymph nodes, and are markedly sensitive to both radiotherapy and chemotherapy. Pure seminomas never produce alpha-fetoprotein, which is why an elevated AFP means the tumour is treated as a non-seminoma regardless of what the microscope shows.
Non-seminomas comprise several tumour types that often occur in combination: embryonal carcinoma, yolk sac tumour, choriocarcinoma, and teratoma. They occur in younger men on average, tend to grow faster, and are more likely to have spread at diagnosis. Choriocarcinoma is the most aggressive component and characteristically produces high beta-hCG levels and spreads through the bloodstream, including to the lungs and brain. Teratoma is unusual: it does not respond to chemotherapy and must be removed surgically, and it retains a small potential to transform into other cancers, which is why residual masses after chemotherapy are resected rather than watched.
Non-germ cell tumours are much less common. Leydig cell and Sertoli cell tumours are sex cord-stromal tumours that are usually benign, though a minority behave malignantly; Leydig cell tumours can produce hormones, causing breast enlargement in adults or early puberty in boys. Testicular lymphoma is the most common testicular malignancy in men over 60, often presents as painless enlargement, and is treated as lymphoma rather than as a testicular cancer.
The risk factors are relatively few and well established.
Cryptorchidism—a testis that did not descend normally into the scrotum—is the strongest. Risk is elevated in the affected testis and, to a lesser degree, in the normally descended one, which suggests an underlying developmental abnormality rather than the position itself being the sole cause. Surgical correction in childhood reduces but does not eliminate the risk, and performing it earlier appears more protective.
A previous testicular cancer raises the risk of a second cancer in the remaining testis, though the absolute risk stays low.
A family history in a father or brother increases risk several-fold, and a brother’s history carries more weight than a father’s, though most men diagnosed have no family history at all.
Infertility and impaired sperm production are associated, consistent with the shared developmental origin.
Certain conditions including Klinefelter syndrome and disorders of sex development carry increased risk. HIV infection is associated with a modest increase in seminoma risk.
Notably absent from this list are the lifestyle factors that dominate risk in many other cancers. Testicular cancer is not meaningfully linked to smoking, alcohol, diet, or exercise. Trauma does not cause it, though an injury sometimes draws attention to a lump that was already present. Vasectomy does not cause it. These points are worth stating because men frequently look for a cause and find none, and the absence of a behavioural explanation is itself accurate information.
The presentation is dominated by one feature that shapes outcomes more than any biological factor: the lump is usually painless.
A firm, painless area or lump within the testis, sometimes noticed incidentally in the shower or by a partner, is the classic presentation. Because it does not hurt, men frequently wait—often for months—assuming that a painless lump cannot be serious. This delay is well documented and is the principal reason a proportion of men present with advanced disease. The essential point is that painlessness is characteristic of the disease rather than evidence against it.
Other presentations include change in the size or consistency of a testis, a heavy or dragging sensation, dull lower abdominal or groin ache, and a new fluid collection around the testis. A minority experience acute pain from bleeding into the tumour. Some tumours produce hormones causing breast tenderness or enlargement.
A meaningful minority present with symptoms of spread before noticing anything in the testis. Testicular cancer drains first to the lymph nodes behind the abdomen near the kidneys—following the testis’s embryonic origin rather than the scrotum’s local drainage—so enlarged nodes there can cause back pain, abdominal fullness, or leg swelling well before a testicular abnormality is noticed. Further spread produces a lump above the collarbone, cough or breathlessness, and general symptoms.
Diagnosis and staging follow a defined sequence.
Scrotal ultrasound with Doppler is the primary imaging test and reliably identifies a solid intratesticular mass, distinguishing it from the far more common benign scrotal conditions.
Serum tumour markers are measured before surgery and are unusually informative in this cancer. Alpha-fetoprotein is produced by yolk sac elements and never by pure seminoma. Beta-hCG can be elevated in both seminoma and non-seminoma, with the highest levels seen in choriocarcinoma. Lactate dehydrogenase reflects tumour bulk and cell turnover. Markers contribute to diagnosis, staging, prognostic grouping, and assessment of response—their decline after treatment is measured against expected half-lives, and a slower-than-expected fall indicates persistent disease. Normal markers do not exclude cancer, since a substantial proportion of tumours produce none.
CT of the chest, abdomen, and pelvis stages the disease. Brain imaging is added when clinically indicated, particularly with choriocarcinoma or very high hCG levels.
Biopsy through the scrotum is avoided. The scrotum and testis have different lymphatic drainage, so violating the scrotum can seed tumour into a compartment it would not otherwise reach. The testis is instead removed through a groin incision with early control of the spermatic cord, and this operation provides both the diagnosis and the primary treatment.
Staging combines the tumour extent, lymph node and distant involvement, and the marker levels—the last being distinctive, as few other cancers incorporate blood markers directly into their staging system. Men with metastatic disease are further classified into good, intermediate, and poor prognosis groups using an internationally agreed system based on marker levels, site of the primary tumour, and pattern of spread, and this grouping determines treatment intensity.
Important to Know
Testicular cancer is one of the genuine success stories of modern oncology, and this deserves to be stated clearly to anyone facing the diagnosis. Cure rates exceed 95% overall, and even men presenting with widespread metastatic disease have a substantial chance of complete cure with cisplatin-based chemotherapy—an outcome that is exceptional among solid cancers. Care is coordinated by urologists and medical oncologists with specific expertise, alongside radiology, pathology, and fertility services.
Radical inguinal orchidectomy is the starting point for nearly all patients. Removing the testis through a groin incision with early clamping of the spermatic cord prevents seeding and preserves normal lymphatic drainage. A prosthesis can be placed at the same operation or later, and it is worth asking about this beforehand rather than afterwards. Losing one testis does not usually affect fertility or testosterone levels, since the remaining testis generally compensates, though this is checked afterwards.
Sperm banking should be discussed and offered before treatment, ideally before the orchidectomy and certainly before any chemotherapy or radiotherapy. Many men already have reduced sperm quality at diagnosis, and treatment can impair fertility further. This conversation is easy to lose in the urgency of a cancer diagnosis, and it is entirely reasonable for a man to raise it himself if it has not been mentioned.
Treatment after orchidectomy is stratified by type and stage, and a key principle of modern practice is giving the least treatment necessary to achieve cure, because the men affected are young and will live for decades with the consequences.
Active surveillance is now standard for many men with stage I disease—cancer confined to the testis with normal post-operative markers and clear scans. Most will never relapse, and those who do can be cured with treatment at that point. Surveillance involves scheduled markers, imaging, and clinical review over several years. Choosing surveillance means accepting regular monitoring in exchange for avoiding treatment that most men do not need, and it does not compromise survival.
Chemotherapy, most commonly cisplatin-based combinations, is highly effective and is used for metastatic disease and for some higher-risk stage I cases. The number of cycles is determined by prognostic grouping.
Radiotherapy retains a role in selected seminomas, though its use has narrowed considerably as concerns about long-term second-cancer risk in young men have grown.
Retroperitoneal lymph node dissection is used in specific situations, including residual masses after chemotherapy in non-seminoma and as primary treatment in selected cases. Nerve-sparing techniques preserve ejaculatory function in most patients when performed by experienced surgeons.
Residual masses after chemotherapy are handled differently by tumour type. In non-seminoma, they are usually resected, because they may contain teratoma—which chemotherapy does not eliminate and which can grow or transform—or viable cancer. In seminoma, residual masses often resolve over time and PET scanning helps determine whether any remaining tissue is active.
Long-term follow-up is important and continues for years. Relapse can occur late and is treatable when detected. Follow-up also monitors the remaining testis, since a second cancer occurs in a small percentage of men.
Late effects of treatment are a genuine consideration given the young age at diagnosis and the long survival that follows. Cisplatin-based chemotherapy is associated with hearing loss and tinnitus, peripheral nerve damage, kidney effects, cardiovascular disease, metabolic changes, and a small increased risk of second cancers. Radiotherapy carries its own second-cancer risk. Testosterone deficiency develops in some men and is worth checking for, since replacement improves energy, mood, sexual function, and bone health where levels are genuinely low. Survivorship care addressing cardiovascular risk, metabolic health, fertility, hormonal status, and psychological wellbeing is a recognised part of management rather than an optional extra.
Psychological impact deserves acknowledgement. A cancer diagnosis at 25 or 30, affecting an organ tied to identity and sexuality, in a group with little experience of serious illness, is genuinely difficult regardless of how good the prognosis is. Anxiety about relapse during surveillance is common and normal. Support services exist and are worth using.
Screening is not recommended for the general population, and routine self-examination has not been shown in trials to reduce mortality. Its practical value lies in familiarity: men who know how their testes normally feel are more likely to notice a change early. Men at higher risk—those with a history of undescended testis, prior testicular cancer, or a strong family history—benefit most from awareness and should have any change assessed promptly.
Care is coordinated by urology and medical oncology, with radiology, pathology, fertility services, and survivorship support. Treatment at centres experienced in this disease is associated with better outcomes, particularly for advanced or complex cases, and referral or a second opinion is reasonable.
Patient education plays an important role. Understanding that painlessness is characteristic rather than reassuring, that biopsy through the scrotum is deliberately avoided, that fertility preservation should come before treatment, that surveillance is an active strategy rather than inaction, and that cure rates remain high even with advanced disease all contribute to appropriate care and informed decision-making.
Red flag symptoms include any new lump, firm area, or change in consistency within a testis, whether or not painful; a testis that has become larger, harder, or noticeably different from the other; a new fluid collection around a testis; persistent back or abdominal pain; a lump above the collarbone; breathlessness, chest pain, or coughing up blood; breast enlargement or tenderness; unexplained weight loss; headaches, visual changes, or neurological symptoms; and, during or after treatment, rising tumour markers or new symptoms. Sudden severe testicular pain with swelling suggests torsion and requires emergency assessment within hours.